Abstract: A sorting system is disclosed, for example for mail items. In the disclosed system, a circulating storage system can receive items from an inlet, and deposit them in an appropriate output receptacle which has been allocated to items in a particular group. For example, the items can be sorted by destination, and each output receptacle can be allocated to a particular destination. In the event that the destination of an item has not output receptacle allocated thereto, the system controller can determine whether to allocate a receptacle, or whether to recirculate the item within the circulating storage system. This possibility allows items to be grouped together within the system, until there are sufficient items for a particular destination to allow them to be handled efficiently, and in particular allows the allocation of output receptacles to destinations to be controlled efficiently.